Pushing the Limits of X-ray Microscopy for 3D Semiconductor Imaging

As semiconductor device architectures advance towards complex 3D geometries, traditional metrology tools such as electron microscopy face fundamental limitations for high-throughput, non-destructive 3D metrology applications. This paper provides an overview of recent innovations in 3D X-ray microscopy that bridge the resolution gap towards electron microscopy, enabling unique, non-destructive 3D metrology. We introduce advanced acquisition and reconstruction methods that improve imaging resolution and enable the inspection of thick samples by overcoming fundamental depth-of-field limits. Furthermore, we demonstrate how imaging throughput can be significantly enhanced by exploiting the inherent Manhattan geometry of lithographic samples. The combination of these factors currently yields isotropic 3D imaging with 4 nm resolution voxels. With the emergence of next-generation X-ray sources, advanced instrumentation, and algorithmic improvements, this resolution is expected to reach 1 nm, enabling non-destructive microchip inspection previously impossible with X-ray or electron microscopy.